Incandescent lamp.



N0. 693,222. -Patented Fe'b.ll, |902.;l

H. BOEHM.

INCANDESCENT LAME.

@Application led Oct. 11, 1901.)

I (No Model.)

v UNITED @rares PATENT OFFICE.

HERMAN BOEHM, OF YOUNGSTOVN, OHIO.

INCAN DESCENT LAM P.

SPECIFICATION forming part of Letters Patent No. 693,222, dated February 1 1, 1902.

Application filed October 11, 1901. Serial No.78,3'73. (No model.) "n

To all wtmn it may concern:

Be it known that I, HERMAN Bonnin, of Youngstown, in the county of Mahoning and State of Ohio, have invented certain new and usefullmprovements in IncandescentLamps; and I do hereby declare the following to be a full, clear, and eXact description of the invention, such as will enable others skilled in the art to which itrappertains to make and use the same.

This invention relates primarily to all classes of small incandescent baseless lamps employed in telephone-switchboards; and the objects of my improvements are to avoid all danger of short-circuiting, breaking of leading-in wires or contact-surfaces, and to insure a perfect fit in the sockets of the base-plate. These sockets are necessarily small in diameter, and it is essential to the securing of good results that the lamps fit snug therein and have perfect contact with the springs forming electrical terminals. These ends are attained by my invention, which will be hereinafter fully set forth, and particularly pointed out in the claims. v

In the accompanying drawings, Figure lis a side elevation on an enlarged scale. Figs. 2 and 3 are cross-sectional views on lines 2 2 and 3 3, Fig. 1. Fig. 4 is a central longitudinal sectional view showing the terminal springs in engagement with the contact-plates of the lamp. Fig. 5 is a side elevation'of a slight modification. Fig. 6 is a cross-section thereof on line 5 5. 1

Referring to the drawings, 1 designates the lamp-bulb; 2, the-mount; 3, the filament, and 4 the leading-in wires. From the point ofunion of the mount and bulb are formed two grooves or indentations 5, which extend longitudinally on opposite sides of the lampbulb the entire or any desired length thereof,

terminating in widened indentations or recesses. The leading-in wires t snug in these grooves, and their ends are held in the recesses by contact-plates 6, which are made of suitable soft metal, cement, or composition of such thickness that they ill the recesses without projecting above or beyond the latter. By thus passing the leading-in wires through the grooves or indentations and holding them by soft-metal plates, cement, or composition sunk in the recesses the lamp presents an exteriorly smooth surface, thereby avoiding the dan ger of the wires being broken or twisted out of place, the happening of which usually causes short-circuitin g. The terminal springs 7 of the electric circuit will engage the contact-plates when the lamp is inserted in position. Y

In lieu of carrying the leading-in wires out through the mount and in grooves or indentations` formed in the end of the lamp-bulb such wires may, as shown in Figs 4t and 5, be passed outwardlythrough opposite openings in the lamp-bulb and secured by contactplates 8 set in recesses in the exterior of the lamp-bulb.

The advantages of my invention are apparent. The lamp will fit snug in its socket, insuring perfect contact, and all danger of breaking the wire and of short-circuiting is avoided. n

' I claim as my .invention- 1 'An incandescent lamp-bulb having re- -cesses in its sides, leading-in wires extended into such recesses, and contact-plates for hold- .ing the Wires, ksuch plates beinglocated within the recesses, as set forth.

2. An incandescent lamp-bulb having in its sides grooves or indentations extending from one end, and leading -in wires extended through and held in said grooves or indentations, as set forth.

An kincandescent lamp-bulb having recesses in its sides, and grooves or indentations extending from one end to and terminating in said recesses, leading-in wires extended through said grooves or indentations, and contact-plates in said recesses holding the ends of said leading-in wires, as set forth.

"In testimony whereof I have signed this specification in the presenceof two subscribing witnesses.

HERMAN BOEIIM. 

